Retractable wall apparatus and drive mechanism therefor



Aug. 8,

R. WARDLAW ETAL RETRACTABLE WALL APPARATUS AND DRIVE MECHANISM THEREFORFiled May 10, 1966 3 Sheets-Sheet 1 FIG .1

ATTORNEYS Aug. 8, 1967 R. WARDLAW ETAL 3,334,725

RETRACTABLE WALL APPARATUS AND DRIVE MECHANISM THEREFOR Filed May 10,1966 3 Sheets-Sheet,

I a an I 2 50 JJ 65 E I aw \Km 1 l 4 70 i v /ls rh :1 L i 56 I4; IVE! 20as I g 76 INVENTORS 7 F FIG 6 RUSSELL WARDLAW 72, v BY CHARLES J.DENNEHY ar- 5 M f ATTORNEYS Aug. 8, 1967 R. WARDLAW ETAL 3,334,725

RETRACTABLE WALL APPARATUS AND DRIVE MECHANISM THEREFOR Filed May 10,1966 3 Sheets-Sheet 3 INVENTORS RUSSELL WARDLAW BY CHARLES J. DENNEHYATTORNEYS United States Patent 3,334,725 RETRACTABLE WALL APPARATUS ANDDRIVE MECHANISM THEREFQR Russell Wardlaw, San Rafael, and Charles J.Dennehy,

San Francisco, Calif., assignors to The Cookson Company, San Francisco,Calif., a corporation of California Filed May 10, 1966, Ser. No. 548,9269 Claims. (Cl. 198-89) This invention relates generally to retractablewall apparatus and to drive mechanisms therefor, and more particularlyto such an apparatus which serves as a movable or collapsable side guardfor a conveyor.

Heretofore, such conveyors have been provided with movable side guardswhich have been moved as the point of feeding the conveyor was changed.Such side guards have not been satisfactory over long runs of conveyorbecause the mass of the side guards made their movement diflicult andslow. There is, therefore, a need for a new and improved retractablewall apparatus and driving mechanism therefor which can be usedconveniently in conjunction with a conveyor system.

In general, it is an object of the present invention to provide aretractable wall apparatus and drive mechanism therefor which overcomesthe above named disadvantages.

Another object of the invention is to provide a wall apparatus of theabove character which is powered so that it closely and rapidly followsthe change in position required when the point of feeding the conveyorsystem is shifted.

Another object of the invention is to provide a wall apparatus and drivemechanism therefor of the above character which forms a continuous guardon both sides of the conveyor system from the point of feeding theconveyor and which is variable in position according to the point offeeding the conveyor.

Another object of the invention is to provide a wall apparatus of theabove character which is simple and low cost in construction and whichis able to withstand rapid and repeated accelerations.

Additional objects and features of the invention will appear from thefollowing description in which the preferred embodiment has been setforth in detail in conjunction with the accompanying drawings.

Referring to the drawings:

FIGURE 1 is a top plan view of a conveyor system including a retractablewall apparatus and drive mechanism therefor, incorporating the presentinvention.

FIGURE 2 is a side elevational view of the system shown in FIGURE 1.

FIGURE 3 is a cross-sectioned view taken along the line 3-3 of FIGURE 2.

FIGURE 4 is an enlarged detail view of the connection between the wallapparatus and the collector trolley of the conveyor system.

FIGURE 5 is an enlarged top plan view of the drive mechanism taken alongthe lines 5-5 of FIGURE 2.

FIGURE 6 is a cross-sectional View taken along the lines 66 of FIGURE 1.

FIGURE 7 is an enlarged detail view, partially in crosssection, of thepartition drive assembly shown in FIG- URE 6.

FIGURE 8 is a detail view of the connection between the tensioning cableand collector trolley shown in FIGURE 1.

In general, the invention consists of a conveyor system in whicharticles are fed to a conveyor belt at a plurality of points therealong,as by a plurality of spaced conveyors. Spaced retractable wall means isdisposed along each side of the conveyor belt for movement therealong.Each wall means is connected with suitable means for forming acontinuous loop and both loops being driven till means.

Referring particularly to the drawings, there is shown a main conveyor10 extending in a generally horizontal direction and which includes abelt 11 which passes about rollers 12 rotatably mounted in a conveyorframework 14. A collector trolley 16 overlies the main conveyor 10 andis adapted to travel longitudinally thereof. The trolley 16 has fourwheels 18 which travel on rails 20 mounted on the framework 14 onopposite sides of the main conveyor belt 10. At spaced locations alongthe length of the main conveyor belt 10 and above the plane of the mainconveyor belt are located a plurality of feeder conveyors 22 includingconveyor belts 24 which pass about rollers 26 rotatably carried in theframeworks 28. Each conveyor 22 is independently driven by suitabledrive means (not shown).

The collector trolley 16 is provided with a belt 30 supported on rollers31 rotatably mounted on the trolley. Belt 30 is adapted to move througha right angle to thereby change the direction of flow of packages fromthat of one of feeder conveyors 22 to conveyor 10. Thus, belt 30overlies conveyor belt 10 at one edge 32 and extends through a rightangle to the next exit end of one of feeder conveyors 24 at its otheredge 34.

Along each side of belt 30 there are provided vertically extendingcurved walls 36 and 38 which are closely spaced to the belt 30 toprevent articles from falling olf the trolley, except by moving towardedge 32. An electric motor 40 is mounted on the collector trolley 16 andis connected through a suitable sprocket chain drive assembly 41 towheels 18 of the trolley for moving the trolley back and forth uponrails 20.

Spaced parallel retractable walls or partitions 42 and 43 are mounted inopposite sides of the main conveyor belt 10 to extend longitudinallythereof. One end of the outer end of walls 42 and 43 are connected tosidewalls 36 and 38 of the trolley by bracket means, comprising rightangle brackets 44, 45 connected by suitable fasteners 46. The walls 42and 43 are mounted for sliding motion on guide shoes 47 which travel inguide tracks 48 mounted on the frame work 14. Each of the walls orpartitions 42, 43 comprises a plurality of vertical members 49 formedand interconnected as shown in FIGURE 4, or they may may be formed asdescribed in US. Patent No. 2,934,139.

The other end of the wall or partition 42, 43 terminates in a coil box50 located beyond the last of the feeder conveyors 22. Since each of thewalls or partitions 42, 43 and coil boxes 50 together with theassociated structure are similar, except as to handedness, the followingdescription will only cover one wall and associated apparatus, the otherwall being understood to be the mirror image of that described.

As shown particularly in FIGURES 1, 2, and 6, the coil box 50 is asubstantially rectangular box having top plate 52, sidewalls 54 andbottom plate 56. A third plate 58 is mounted by suitable framework (notdetailed) in spaced relation below the bottom plate 56. A verticalopening 59 is formed in the sidewall of the box adjacent the track 20for permitting the retractable wall 42 to pass into the box.

As it enters coil box 50, wall 42 travels over an idler barrel 62mounted for rotation between top and bottom plates 52, 56. A coil barrel64 is rotatably mounted within the coil box on a shaft 65 rotatablymounted in bearings 66 and 68. Wall 42 is secured to barrel 64 and isadapted to be wrapped around the same, its lower extremities beingsupported by a flat circular disk 70 afiixed to the bottom of the barrel64. The shaft 65 upon which the barrel is mounted extends through thebearing 68 and bottom plate 56 and carries therebelow a gear 71 keyedand pinned thereto. A shaft 72 is rotatably mounted in bearings 74secured to the bottom plate 56 and the third plate 58 and carries aspeed changing gear 76 and a sprocket 78, each keyed and pinned to shaft72.

Another shaft 80 is rotatably mounted in bearings 82 carried by thebottom plate 56 and third plate 58 and has a conical scroll or spool 84keyed and pinned thereto at its top and centered thereon by a bushing 86at its bottom. A sprocket 88 is keyed and pinned to shaft 80. A chain 90is trained about the sprocket 78 and 88 and a tensioning sprocket 92 torotatably connect the shaft 80 with shaft 72. Thus, rotation of shaft 65causes rotation of the scroll 84 in the same sense of rotation and viceversa.

The scroll 84 is shaped in the form of a truncated cone having ahelico-conical groove 102 extending from the bottom to the top andfacing outwardly thereabout for receiving a tensioning cable 103. Thecable 103 is afiixed to the bottom or large end of the scroll 84 and isentrained in groove 102. 7

Cable 103 is reeved over pulleys 104 and has its other end 105 securedto adjustable tensioning means 106 (FIGURES 1, 8) carried by trolley 16.Tensioning means 106 include eye bolt 107 about which the cable issecured by a conventional cable clamp 110. The threaded end of the eyebolt passes through a bracket 112 secured to trolley 16 and is held intension by a compression spring 114 abutting a bracket 112 at one endand a washer 116 at the other end, washer 116 being held on the bolt bya nut 118. Thus, tension force is transmitted from the outer end of thepartition 42 through bracket 49 to trolley 16, from the trolley tobracket 112 and tensioning means 106 through cable 103 to the scroll 84,gearing and barrel 64 to thereby form a continuous loop in tension.Thus, wall 42 is maintained under constant, fixed tension.

Operation and use of the side coiling partition may now be brieflydescribed as follows: Let it be assumed that walls 42 and trolley 16 areat rest, the cables 103 and walls 42 being placed under the desiredamount of tension by the tensioning means 106. Actuation of the trolleymotor 40 in one sense causes the trolley 16 to pull the walls 42 awayfrom the coil boxes 50. This motion is transmitted by the partitions 42to the coiled portion and in turn through the gear means to the scroll84 to cause the scroll 84 to pull in cables. Since the winding of thescroll 84 is from the large diameter end to the small diameter end, itis obvious that less and less cable per revolution is pulled in as thepartitions 42 are pulled out; and, this corresponds to the fact thatless and less partition per revolution is rolled off of the coiledportion of the partition as thediameter of the coiled por-, tion of thepartitions decreases. Actuation of the motor 40 in the opposite sensecauses the trolley 16 to pull on the upperrun of cable 103 and to causethe cable to be pulled off scroll 84. In turn, the scroll 84 rotates andoperates the gear means and coil barrel to take up wall 42. As the wallsare coiled up, the diameter of the coiled portion of the wall increasesso that more and more cable per revolution is let out to maintainconstant tension. Since the cable is let out from lower, larger diameterportions of the scroll, a larger amount per revolution is let out tothereby automatically compensate for the larger amount of walls 42 beingcoiled up per revolution.

With the construction of the present invention, the tension can bemaintained at a fixed value despite the changing diameter of the coilingpartition. This is possible because of the continuously changingdiameter of the groove 102 formed in the scroll 84 which permits payingout of cable at a rate proportional to the rate of take up of partition.The scroll is dimensioned so that the groove has a diameter equal to l/N of the maximum- .minimum diameters of the coiled partition of thebarrel at its top and bottom, respectively, N being the gear ratiobetween the barrel and the scroll. Since the circumference of the circleis linearly related to the diameter, it is easily seen that the changein diameter of the scroll is a linear property so that the groove on thescroll generally lies on the surface of a right circular cone.Preferably, the gear ratio is arranged so that the scroll rotates fasterthan the barrel whereby the scroll can be made considerably smaller andyet not be any less effective.

The tension set up is maintained by the present construction under allconditions, i.e., regardless of the direction of motion of the trolleysince all of the connections are designed and constructed for completelyreversible operation.

It is apparent from the foregoing that we have provided a partition orwall apparatus and drive means therefor which has particular advantagesover prior structures. The construction of this invention utilizes adrive mechanism in the form of a trolley or other means for pulling atthe outer end of the walls. During coiling and uncoilng, the walls aremaintained under constant tension by the action of the scroll and cabledespite the changing diameter of the coiled portion of the partition andin either direction of motion of the walls. Although a trolley and motorhave been shown as the driving mechanism for the walls, it is apparentthat the walls and cable could be pulled by hand or other means.

We claim:

1. In a retractable wall apparatus, a conveyor extending in a generallyhorizontal direction and adapted to have articles supplied thereto at aplurality of points spaced along the conveyor, retractable wall meansdisposed along each side of the conveyor to form a side guard for theconveyor, said retractable wall means having inner and outer ends, meansmounting the retractable wall means to permit movement thereof and topermit the conveyor to be loaded with articles at various positions, atrolley secured to the outer ends of said retractable wall means andadapted for travel longitudinally of the conveyor, cable-like meanshaving one end secured at the trolley and means forming a connectionbetween the other end of the cable-like means to the inner ends of thewall means to thereby form a continuous loop, and means driving saidretractable wall means from a single power source provided on thetractor so that said retractable wall means .is selectively drivenpositively in either direction along said conveyor.

2. Apparatus as in claim 1 wherein said means forming a connectionbetween the cable-like means and the inner ends of the wall includes abarrel, means securing the inner end of the retractable wall means tothe 7 barrel, a cable receiving scroll, means rotatably mounting thecable receiving scroll, means forming an operative connection betweenthe barrel and said scroll, said scroll being formed to compensate forchanges in diameter of the retractable wall means as it is coiled ontoand uncoiled from the barrel.

3. In retractable wall apparatus, a framework having an opening therein,a barrel rotatably mounted in said framework, flexible wall means havingone end secured to said barrel and adapted to be coiled thereon throughthe opening in the framework, a cable receiving scroll rotatably mountedon said framework, means forming an operative connection between saidbarrel and said scroll whereby as said scroll is rotated said barrel isrotated, means including flexible cable-like means connected betweensaid scroll and the free end of said Wall means, said cable-like meansbeing adapted to be coiled on said scroll and said scroll being formedin the shape of a truncated cone and having a helico-conical outwardlyfacing groove therein for receiving said cable-like means, and means fordriving said wall means from a single power source for coiling said wallmeans on and uncoiling said wall means from said barrel as said scrollis rotated, the eifective diameter of the groove in the scrollautomatically changing to compensate for the changing diameter of thecoiled portion of the wall means.

4. Apparatus as in claim 3 wherein said scroll has a maximum diameterl/N times the maximum diameter of the wall means on the barrel, and aminimum diameter l/N times the minimum diameter of the barrel where l/Nrepresents the ratio of rotation between the scroll and the barrel asestablished by the means forming an operative connection.

5. Apparatus as in claim 3 wherein the connecting mean also includes atrolley, track means on which said trolley travels, means connecting theouter end of said wall means to said trolley, and means connecting saidcable-like means to said trolley, and wherein said means for drivingsaid wall means is mounted on said trolley to move said trolley and thewall means and cable-like means secured thereto.

6. Apparatus as in claim 3 wherein said means forming an operativeconnection includes a shaft extending axially of said barrel, andgearing means connecting said scroll to said shaft.

7. Apparatus as in claim '3 in which the gearing connecting said scrollto said barrel has a gear ratio such that said scroll rotates fasterthan said barrel.

8. In a retractable wall apparatus, a conveyor extending in a generallyhorizontal direction and adapted to have articles supplied thereto at aplurality of points spaced along one side of the conveyor, wall meansdisposed along each side of the conveyor to form side guards for theconveyor, at least one of said wall means being retractable and havinginner and outer ends, a framework having an opening therein, a 'barrelrotatably mounted in said framework, the outer end of said wall meansbeing secured to said barrel and adapted to be coiled thereon throughthe opening in the framework, a cable receiving scroll rot-atablymounted in said framework, means forming an operative connection betweensaid barrel and said scroll whereby as said scroll is rotated saidbarrel is rotated, cable-like means forming a flexible connection undertension between the scroll and the outer end of said wall means, saidcable-like means being coiled on said scroll such that as theretractable wall is coiled onto or uncoiled from the banrel and thediameter of the coiled portion of the wall changes, the changingdiameter is automatically compensated for by a changing of position ofthe cable-like means on said scroll to thereby maintain the tension insaid cable means at a substantially constant level, and means connectedto the outer end of the retractable wall means for driving the same backand forth.

9. In retractable wall apparatus, an elongate moving conveyor extendingin a generally horizontal direction, a plurality of stations positionedat spaced locations alongside said conveyor of selectively deliveringarticles to the conveyor at any one of said locations, retractable wallmeans disposed along each side of the conveyor to form a side guard forpreventing articles delivered to the conveyor from falling ofi of thesame, said retractable Wall means having inner and outer ends, the outerends being displaced away from the inner ends in the direction of motionof said conveyor, said wall means including means forming a connectionbetween the inner and outer ends thereof so that said wall means withthe means forming the connection make up a continuous loop, meansmounting said retractable wall means for movement alongside the conveyorso that the inner ends are posi-, tionable at a preselected station, andmeans for driving said wall means from a single power source so that theretractable wall means is driven positively in either direc tion backand forth in the mounting means between a position of rest at any givenstation to a position of rest at another station, the inner ends of saidwall means being constructed so that the moving conveyor can receivearticles from the station at which the inner ends of said wall means ispositioned.

References Cited UNITED STATES PATENTS 1,425,556 8/1922 Johnson 19879FOREIGN PATENTS 707,896 4/1954 Great Britain.

EVON C. BLUNK, Primary Examiner. RICHARD E. AEGERTER, Examiner.

1. IN A RETRACTABLE WALL APPARATUS, A CONVEYOR EXTENDING IN A GENERALLYHORIZONTAL DIRECTION AND ADAPTED TO HAVE ARTICLES SUPPLIED THERETO AT APLURALITY OF POINTS SPACED ALONG THE CONVEYOR, RETRACTABLE WALL MEANSDISPOSED ALONG EACH SIDE OF THE CONVEYOR TO FORM A SIDE GUARD FOR THECONVEYOR, SAID RETRACTABLE WALL MEANS HAVING INNER AND OUTER ENDS, MEANSMOUNTING THE RETRACTABLE WALL MEANS TO PERMIT MOVEMENT THEREOF AND TOPERMIT THE CONVEYOR TO BE LOADED WITH ARTICLES AT VARIOUS POSITIONS, ATROLLEY SECURED TO THE OUTER ENDS OF SAID RETRACTABLE WALL MEANS ANDADAPTED FOR TRAVEL LONGITUDINALLY OF THE CONVEYOR, CABLE-LIKE MEANSHAVING ONE END SECURED AT THE TROLLEY AND MEANS FORMING A CONNECTIONBETWEEN THE OTHER END OF THE CABLE-LIKE MEANS TO THE INNER ENDS OF THEWALL MEANS TO THEREBY FORM A CONTINUOUS LOOP, AND MEANS DIRIVING SAIDRETRACTABLE WALL MEANS FROM A SINGLE POWER SOURCE PROVIDED ON THETRACTOR SO THAT SAID RETRACTABLE WALL MEANS IS SELECTIVELY DRIVENPOSITIVELY IN EITHER DIRECTTION ALONG SAID CONVEYOR.